Issues Dealing With Safe Handling of Mercury

Issues Dealing With Safe Handlingof Mercury Philip T. Spampinato (spampinatop@ornl.gov, 865-576-5267) Tony A. Gabriel (gabrielta@ornl.gov, 865-574-6082) Meeting on High-Power Mercury Jet Experiment May 26-27, 2004 CERN Geneva, Switzerland

Outline • Properties, Safety Limits and Standards • SNS Target Test Facility/WNR • Installing Hg into the TTF • Standard Hg Containers/Pallets • Monitoring Hg Vapors • SNS Hg Experience Installing New Equipment • Conclusions

Properties, Safety Limits, Standards • Atomic Weight: 200.59 • Boiling Point: 357 degree C • Specific Gravity: 13.6 • Vapor Pressure: 0.0012 mm Hg • Vapor Density: 7.0 • Vapors: colorless, odorless • Solubility: insoluble in water • NIOSH/OSHA: 0.05 mg/m^3, 10 h/day; 40 h/wk • Max. permissible exposure <0.10 mg/m^3

Table 1. Mercury Health Effects Exposure Route Acute Effects Chronic Effects Ingestion Acute poisoning following ingestion causes metallic taste, thirst, abdominal pain, vomiting, and diarrhea. May damage kidneys and central nervous system. Death may occur from uremia. Chronic ingestion causes skin disorders, salivation, diarrhea, anemia, leukopenia, liver and kidney damage. Skin Contact May be absorbed through the skin causing effects similar to those of acute inhalation. May be absorbed through the skin causing effects similar to those of chronic inhalation. Eye Contact May cause irritation. None known. Inhalation Inhalation of vapor results in dyspnea, cough, fever, nausea, vomiting, diarrhea, stomatitis, salivation, and metallic taste. Pulmonary disturbances may follow. Anuria may occur. May damage the lungs, liver, kidneys, central nervous system and reproductive system. Chronic inhalation may result in tremors, salivation, stomatitis, loosening of the teeth, blue gum line, peripheral neuropathy, nephritis, diarrhea, anxiety, headache, weight loss, anorexia, and psychic disturbances. Most Likely Routes of Entry Ingestion, skin absorption, inhalation of vapors Mercury Health Effects

Exposure Route Treatment Ingestion Induce vomiting. Get medical attention immediately. Skin Contact Remove contaminated clothing and shoes immediately. Wash affected area with soap or mild detergent and large amounts of water until no evidence of chemical remains (approx. 15-20 minutes). Get medical attention immediately. Eye Contact Wash eyes immediately with large amounts of water or normal saline, occasionally lifting upper and lower lids, until no evidence of chemical remains (approx. 15-20 minutes). Get medical attention immediately. Inhalation Remove from exposure area to fresh air immediately. If breathing has stopped, give artificial respiration if qualified personnel are available. Maintain airway and blood pressure and administer oxygen if qualified personnel are available. Keep affected person warm and at rest. Get medical attention immediately. Mercury First Aid Instruction

Mercury Vapors • Look at video clip that shows Hg vapors http://www.deq.state.mi.us/documents/deq-ead-p2-mercury-bb-Vapors.wmv

The Target Test Facility (TTF)Background Information • Full scale, prototype of SNS Hg flow loop • 1400 liters of Hg • Used to determine flow characteristics • Develop hands on operating experience • Assess key remote handling design issues

TTF Pump Room and Target Room • 75 Hp centrifugal pump • Nominal flow at 1560 liters/s (380 gpm) • Completed several upgrades to the piping and target configuration

Mercury Containers/Shipping • 2 liter standard flask • Flask weighs ~165 kg

TTF Operations – Hg Filling • Peristaltic pump was successfully tested • Tipping fixture was tested but not used

Filling (cont.) • TTF vacuum pump was used to transfer Hg directly into the storage tank • Lower risk than using the peristaltic pump • Faster operation, ~ 1-1/2 minutes per flask

Category1 Activity Hg Vapor Level (mg/m3) Access & PPE Requirements Hg Vapor Level (mg/m3) Access & PPE Requirements I Visitor / walkthrough < 0.012 Shoe Covers Gloves Lab coat 0.012 No Visitor Access II Light hands-on (target room sensor adjustments, vacuum pump operation, etc.) < 0.012 Cat I Requirements 0.012 Shoe Covers Gloves Lab coat over Company-issued clothing Respirator2 III Opening “minor” (≤1" in diameter) components in mercury system < 0.012 Cat I Requirements + Company Clothing 0.012 Cat II Requirements IV Maintenance / cleanup activities (opening flanges, spill containment, etc.) < 0.012 Cat I Requirements + Company Clothing + Coveralls in lieu of lab coat 0.012 Cat II Requirements + Coveralls in lieu of lab coat Notes: 1. Access requirements for any activities not clearly falling into one of the above categories or if the Hg vapor level is at or exceeds 1.25 mg/m3 will be evaluated on a case-by-case basis 2. Respirator usage not required if portable Hg vapor monitor readings in the immediate work area are less than 0.012 mg/m3 3. Portable Hg vapor monitoring shall be performed for all Category III & Category IV operations. Local ventilation also required. TTF Access and Personal Protective Equipment – Minimum Requirements

Mercury Monitoring • TTF Uses Three Jerome 431-X Vapor Analyzers • One monitor dedicated to each room, connected to the Target Test Facility PLC • A portable monitor used during interventions • The Jerome analyzer has a range of 0.000 – 0.999 mg/m3 • Sensitivity is 0.003 mg/m3 • Measures the change in resistance across a gold film as a function of Hg vapor • Many other monitors are available

Equipment Experience: Installation of He Bubbler • Bubbler test equipment was recently added to TTF • He leak tested all joints at 25 psig before filling with Hg

Proper Dressing Is Mandatory • Overalls, gloves, and overshoes are the minimum requirement

TTF Operations - Containment • You cannot have too much containment!

Mercury Puddling • Mercury will collect into small droplets and large puddles even in pipes sloped at 1 degree

Mercury Decontamination/Cleanup • HgX is a water soluble, metallic-mercury/sulfide converting powder with a chelating compound and dispersing agent • Forms a film over finely divided Hg beads, producing a non-vaporizing sulfide • Mix with water as needed • Apply with sponge • Low cost

Mercury Decon/Cleanup (cont.) • HEPA Vacuum • RCRA and non-RCRA waste collection

TTF Ventilation System • 5 air changes/h • Flow velocity at 25-32 ft/s • Sulfide-impregnated charcoal filter in line with the building ventilation

Hg Was Used As An Anti-Friction Medium • Hg was used as bearing material in lighthouse lamp mechanisms • the rotating mechanism floated in Hg

Small quantity of Hg was released somehow from handling the target Vapor monitor would have alerted the presence of Hg Herculite taped to floor area ~3 x 10^3 dpm/100 cm^2 contamination level Handling Activated Hg AddsAnother Level of Concern

One person’s clothing was given up Everyone’s shoes were given up Contamination level although very low, was reportable Calculated to be micro- or pico-grams ?? Activated Hg (cont.)

Conclusions • ORNL has extensive experience handling Hg based on operating the TTF and other smaller test loops • 1400 liters, full scale SNS flow loop • Hg was installed with a vacuum pump; extensive use of spill containment; He leak check before operating • Developed procedures for operating TTF and safe handling of Hg • Numerous interventions have been undertaken to add/modify TTF test equipment • Experience with dismantling pipe flanges, pipe cutting, and welding • Vapor monitors always in use; decontamination using HgX and HEPA vacuum • Handling activated mercury requires these same precautions and procedures, at an even higher level of alertness

Issues Dealing With Safe Handling of Mercury